US4792592A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for reducing sheeting during polymerization of alpha-olefins
Assignee: Union Carbide Corp
•
Filing: 1985-05-06
•
Granted: 1988-12-20
•
Expires: 2005-05-06
Abstract
Abstract A process for reducing sheeting during production of polyolefins by polymerization of alpha-olefins utilizing titanium based polymerization catalysts wherein the static electric charges in the reactor at the site of possible sheet formation are maintained below static voltage levels which would otherwise cause sheet formation.
Inventors
- 👤 Bernard D. Fulks
- 👤 Steven P. Sawin
- 👤 Collin D. Aikman
- 👤 John M. Jenkins, III
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 15:38
CPC Classifications
B; B01; B01J; B01J8/00; B01J8/18; B01J8/1809; C; C08; C08F; C08F10/00; B01J2208/00; B01J2208/00008; B01J2208/00017; B01J2208/00106; B01J2208/00168; B01J2208/00256; B01J2208/00265; B01J2208/00274; B01J2208/00734; C08F110/00; C08F110/02; C08F210/00; C08F210/16; C08F2410/00; C08F2410/01; C08F4/00; C08F4/42; C08F4/44; C08F4/60; C08F4/62; C08F4/639; C08F4/63912; C08F4/6392; C08F4/63922; C08F4/63925; Y; Y10; Y10S; Y10S526/00; Y10S526/901
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
76 words
In a method for polymerization of one or more alpha-olefins in a fluidized bed reactor in the presence of a catalyst prone to cause sheeting, the improvement which comprises maintaining the static electric charge in said reactor at the site of possible sheet formation below a static voltage level which would otherwise permit sheeting to occur, by means for creating areas of localized field strength within said reactor for the promotion of electrical discharge to ground.
Claim 2
Dependent Claim
76 words
In a method for polymerization of one or more alpha-olefins in a fluidized bed reactor in the presence of a catalyst prone to cause sheeting, the improvement which comprises maintaining the static electric charge in said reactor at the site of possible sheet formation below a static voltage level which would otherwise permit sheeting to occur, by means for creating areas of localized field strength within said reactor for the promotion of electrical discharge to ground.
Claim 3
Dependent Claim
49 words
A method according to claim 1 wherein said method is for the production of an alpha-olefin linear homopolymer of ethylene or a linear copolymer of a major mol percent (90%) of ethylene, and a minor mol percent (10%) of one or more C 3 to C 8 alpha olefins.
Claim 4
Dependent Claim
32 words
A method according to claim 1 wherein said method is for the production of a homopolymer or copolymers of propylene, with one or more of butene-1, pentene-1, hexene-1, 4-methylpentene-1, heptene-1, or octene-1.
Claim 5
Dependent Claim
13 words
A method according to claim 1 wherein said catalyst comprises a titanium-based catalyst.
Claim 6
Dependent Claim
66 words
A process for reducing sheeting during polymerization of alpha-olefins in a fluidized bed reactor utilizing titanium-based polymerization catalyst, which comprises maintaining the static electric charge in said reactor at the site of possible sheet formation below a static voltage level which would otherwise permit sheet formation, by means for creating areas of localized field strength within said reactor for the promotion of electrical discharge to ground.
Claim 7
Dependent Claim
66 words
A process for reducing sheeting during polymerization of alpha-olefins in a fluidized bed reactor utilizing titanium-based polymerization catalyst, which comprises maintaining the static electric charge in said reactor at the site of possible sheet formation below a static voltage level which would otherwise permit sheet formation, by means for creating areas of localized field strength within said reactor for the promotion of electrical discharge to ground.
Claim 8
Dependent Claim
48 words
A process according to claim 5 wherein said process is for the production of an alpha-olefin linear homopolymer of ethylene or a linear copolymer of a major mol percent (90%) of ethylene, and a minor mol percent (10%) of one or more C 3 to C 8 alpha-olefins.
Claim 9
Dependent Claim
32 words
A process according to claim 5 wherein said process is for the production of a homopolymer or copolymer of propylene, with one or more of butene-1, pentene-1, hexene-1, 4-methylpentene-1, heptene-1, or octene-1.
Claim 10
Dependent Claim
41 words
A process according to claim 5 in which said titanium-based polymerization catalyst comprises at least one itanium compound, at least one magnesium compound, at least an electron donor compound, at least one activator compound, and at least one inert carrier material.
Claim 11
Dependent Claim
67 words
A process according to claim 8 in which said titanium compound has the structure: Ti(OR).sub.a X.sub.b wherein R is a C 1 to C 14 aliphatic or aromatic hydrocarbon radical, or COR' where R' is a C 1 to C 14 aliphatic or aromatic hydrocarbon radical; X is Cl, Br, or I, a is 0 or 1, b is 2 to 4 inclusive, and a+b=3 or 4.
References Cited (Backward Citations)
US3879362A
Cited
US3922322A
Cited
US3976632A
Cited
US4035560A
Cited
US4152502A
Cited
EP0005215A2
Cited
EP0008799A1
Cited
JPS564608A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1991-12-20 | 1992-06-20 | 1992-12-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-12-20 | 1996-06-20 | 1996-12-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1999-12-20 | 2000-06-20 | 2000-12-20 | $7700.00 | Window Closed / Lapsed |